Aliphatic nitriles, RCN (R = Me, Prn, CH2Cl, and CCl3), in the presence of trifluoromethanesulphonic acid have been found to react with a number of mono-, di-, and tri-substituted phenols and phenol ethers at room temperature to give ketones after hydrolysis of the reaction mixture. Moderate to good yields of acylation products are obtained in the majority of these reactions. The yield with malononitrile and succinonitrile, which are only slightly soluble in the reaction medium, are generally poor, and reaction involves only one of the available nitrile groups. Attempts to use diethyl ether and dichloromethane as solvents for some of these reactions were unsuccessful, but limited success was achieved with nitromethane.